Polyporus squamosus (Huds.) Fr from different origins: chemical characterization, screening of the bioactive properties and specific antimicrobial effects against Pseudomonas aeruginosa

Wild mushrooms are mainly collected during the rainy season and valued as a nutritious food and sources of natural medicines and nutraceuticals. The aim of this study was to determine the chemical composition and bioactive properties (antioxidant, antimicrobial and cytotoxicity) of Polyporus squamosus from two different origins, Portugal and Serbia. The sample from Portugal showed higher contents of as protein (17.14 g/100 g), fat (2.69 g/100 g), ash (3.15 g/100 g) and carbohydrates (77.02 g/100 g); the same sample gave the highest antioxidant activity: highest reducing power, DPPH radical scavenging activity, and lipid peroxidation inhibition in both β-carotene/linoleate and TBARS assay. These results could be related to its higher content in total tocopherols (1968.65 μg/100 g) and phenolic compounds (1.29 mg/100 g). Both extracts exhibited antibacterial activity against all the tested organisms. The samples from Serbia gave higher overall antibacterial activity and showed excellent antibiofilm activity (88.30 %). Overall, P. squamosus methanolic extracts possessed antioxidant, antimicrobial, antibiofilm and anti-quorum sensing activity, and without toxicity for liver cells. This investigation highlights alternatives to be explored for the treatment of bacterial infections, in particular against Pseudomonas aeruginosa. This study provides important results for the chemical and bioactive properties, especially antimicrobial activity of the mushroom P. squamosus. Moreover, to the authors’ knowledge this is the first report on sugars, organic acids, and individual phenolic compounds in P. squamosus.

Extraction, identification, fractionation and isolation of phenolic compounds in plants with hepatoprotective effects

The liver is one of the most important organs of human body, being involved in several vital functions and regulation of physiological processes. Given its pivotal role in the excretion of waste metabolites and drugs detoxification, the liver is often subjected to oxidative stress that leads to lipid peroxidation and severe cellular damage. The conventional treatments of liver diseases such as cirrhosis, fatty liver and chronic hepatitis are frequently inadequate due to side effects caused by hepatotoxic chemical drugs. To overcome this problematic paradox, medicinal plants, owing to their natural richness in phenolic compounds, have been intensively exploited concerning their extracts and fraction composition in order to find bioactive compounds that could be isolated and applied in the treatment of liver ailments. The present review aimed to collect the main results of recent studies carried out in this field and systematize the information for a better understanding of the hepatoprotective capacity of medicinal plants in in vitro and in vivo systems. Generally, the assessed plant extracts revealed good hepatoprotective properties, justifying the fractionation and further isolation of phenolic compounds from different parts of the plant. Twenty-five phenolic compounds, including flavonoids, lignan compounds, phenolic acids and other phenolic compounds, have been isolated and identified, and proved to be effective in the prevention and/or treatment of chemically induced liver damage. In this perspective, the use of medicinal plant extracts, fractions and phenolic compounds seems to be a promising strategy to avoid side effects caused by hepatotoxic chemicals.

Aqueous solubilities of five N-(diethylaminothiocarbonyl)benzimido derivatives at T = 298.15 K

N-(diethylaminothiocarbonyl)benzimido derivatives are polar multifunctional substances. A set of these compounds was synthesised by successive substitution on the enamine side, resulting in similar substances with different polarities, providing a set of model compounds with respect to the study of substituent effects on physico-chemical properties. Experimental aqueous solubility data, at T = 298.15 K, of N-(diethylaminothiocarbonyl)benzamidine, PhCNH2NCSNEt2 (1),N-(diethylaminothiocarbonyl)-N'-phenylbenzamidine, PhCNHPhNCSNEt2 (2), N-(diethylaminothiocarbonyl)-N'-monoethylbenzamidine, PhCNHEtNCSNEt2 (3), N-(diethylaminothiocarbonyl)-N',N'-diethylbenzamidine, PhCNEt2NCSNEt2 (4), and N-(diethylaminothiocarbonyl)benzimido ethylester, PhCOEtNCSNEt2 (5) were measured at T = 298.15 K. The obtained data are supplemented by COSMO-RS aqueous solubility predictions as well as other environmentally important partition coefficients. This information is shown in a two-dimensional chemical space diagram, providing indications about the compartment into which the bulk of the compounds is likely to concentrate. The expected quality of COSMO-RS predictions for this type of screening exercise is illustrated on a set of pesticides with established thermophysical property data.